The 21st century saw the boom of the social networking industry. Online social communities have formed and flourished, bridging that space between and among people from different ages, race, and gender. Dozens of social networking sites are now catering to the hobbies and interests of millions of users all over the world.

Social networking began with Classmates.com in 1995. This site's goal is to help its members find, connect, keep in touch, and form a network with friends and acquaintances from preschool through college, from work, or from the military.

Unlike other networking sites that gained popularity in recent years, Classmates.com uses real names instead of screen names. It also has a rigid privacy policy - the contact information of the member is never revealed within the network unless disclosed one on one by the account owner to another member.

Another social network, SixDegrees.com, emerged in 1997. SixDegrees allows its users to send messages or post bulletins to a list of friends or family members found within their network. SixDegrees faced its early demise four years later, just as the Friendster online community was starting to flourish.

With Friendster, you can invite and add as many friends as you want. You can also upload photos, write blogs and reviews, instant-message other members from your network, and form online groups with those who share the same interests as you have.

At present, Friendster's social network has more than 40 million registered users. Until around April 2004, Friendster was on the top lead among dozens of other social networking sites. MySpace overtook Friendster in terms of page views, and many other social networking sites like Multiply and Hi5.

MySpace is one of the most popular websites in the Internet these days. Just like Friendster, it allows you to collect a network of friends and share blogs, photos, music, and videos with them. This social networking website is very much popular on English speaking countries, while most people from Asia prefer to use Friendster. MySpace already has more than a hundred million members in 2006.

The two major search engines, Google and Yahoo!, have launched their own social networking sites - orkut and Yahoo! 360?. Most blogging sites also allow you to create a network of friends online.

The thing is, most social networking sites work similarly ? they all allow users to expand their network by inviting friends or acquaintances and to share information over the Internet. When you post blogs or files in your account, everyone from your network of friends will be informed of the update through RSS feeds. You also have the option to keep a particular post private to just a few individuals in your network.

Social networks are the best way to increase the number of people in which you are connected with, so if you are into business, you might as well get yourself into social networking to promote your product and increase your sales.

You can choose from hundreds social networking websites available in the web today. However, you might prefer to use a particular networking site in which a lot of your personal friends and contacts are already members. In this way, it's much easier for you to expand your network and share the contents of your site to other users.